We discuss the clinical approach to evaluation and management of neonatal jaundice. We are joined by Jessica Morse, MD, Assistant Professor of Neonatal-Perinatal Medicine at the University of Texas Southwestern Medical Center, and Medical Director of the Parkland Memorial Hospital Newborn Nursery.
Dr. Neeta Goli:
Welcome to Newborn News, a podcast where we discuss educational topics for medical professionals who care for newborns. I'm your host Dr. Neeta Goli, a pediatrician in the UT Southwestern newborn nursery.
Dr. Neeta Goli:
Welcome back to the podcast. In our previous episode we discussed the history and pathophysiology of neonatal hyperbilirubinemia, or jaundice. Today we will discuss the evaluation and management of jaundice. We're joined again, today, by Dr. Dr. Jessica Morse, the medical director of the Parkland newborn nursery. Thanks for being here today.
Dr. Jessica Morse:
Thanks for having me again.
Dr. Neeta Goli:
Now that we understand the pathophysiology of jaundice, what are some practical tips for monitoring jaundice in the newborn nursery?
Dr. Jessica Morse:
The first thing what you want to do when you are monitoring a neonate for jaundice is you want to always visually assess during your daily exams on these babies. And so, when you visually assess, always keep in mind that jaundice progresses in a cephalocaudal manner. In other words, it starts from the head and progresses down to the feet. The hands and the feet, or the extremities, are the last thing that will become jaundice. Oftentimes, families, the first thing that they notice is they will notice scleral icterus as their babies become more and more jaundiced. That is typically the last thing to go away as the jaundice resolves.
Dr. Jessica Morse:
The other thing, some tips and tricks. When you visually assess a neonate, it's often very difficult to try to determine the level of jaundice. We often find that medical students and residents have a difficult time trying to assess for jaundice. Historically, we do know that visual assessment of jaundice has not been very reliable or a reliable tool. However, it can give you somewhat of a guide to be able to determine how significant the jaundice is, but your visual assessment should not be used to make treatment decisions.
Dr. Jessica Morse:
One of the things that I often have our med students or residents do when they're assessing for jaundice is knowing that the extremities are the last thing to become jaundiced. I'll will ask them to put the baby's hand next to their face, because typically, most of our babies will have some sort of facial jaundice typically by day two of life. You can oftentimes visually see the difference in coloration between the hand and the face. The other thing that you can do is you can have them push on the skin, or blanch the skin, and as you push on the skin, you'll notice that the jaundice can become a little bit more apparent. Again, our visual assessment is not a very reliable tool for determining jaundice.
Dr. Jessica Morse:
So then, as you're assessing for jaundice, you want to make sure that you follow your institution protocols when it comes to you assessing jaundice on our neonates. At Parkland, we do a daily transcutaneous bilirubin every morning, and that is plotted on the Bhutani hyperbilirubinemia nomogram. If you look at the Bhutani hyperbilirubinemia risk stratification nomogram, you'll notice that you will plot this serum bilirubin on the Y axis and the postnatal age on the X axis.
Dr. Jessica Morse:
If you look, you want to know what your serum bilirubin is and then how old the baby is. As you can see on this nomogram, you can then stratify this baby into low risk, low intermediate risk, high intermediate risk, or high risk. What this tells you is the likelihood, or the risk that they will develop a significant hyperbilirubinemia that you will need to intervene. Also of note on this nomogram, you want to pay attention that it only begins when the baby is 12 hours of life.
Dr. Jessica Morse:
What you want to do is you want to make sure that you get a transcutaneous bilirubin, which is what we do at Parkland, and then we look at the Bhutani hyperbilirubinemia risk stratification nomogram. If we notice that the TcB, or the transcutaneous bilirubin, is in what we call zone three, or the high intermediate risk zone, or zone four, the high risk zone, then we draw a serum bilirubin, because these curves are based off of a serum and not a transcutaneous. We often know that the transcutaneous bilirubin, once you get on the very high end and on the very low end, it doesn't tend to be as accurate. So you want to make sure that you're making treatment decisions based off an accurate measurement.
Dr. Jessica Morse:
Once we have the serum bilirubin, we then go back to the Bhutani hyperbilirubinemia risk stratification nomogram and see where they fall, either in zone one, zone two, zone three, or zone four. If this baby also has a significant hyperbilirubinemia, in other words, if we notice that the transcutaneous bilirubin is in zone three or in zone four, you also might want to go and look at the mother's blood type. Again, because one of the pathologic causes of hyperbilirubinemia in neonates is ABO incompatibility, so you want to go ahead and get a cord blood workup if mom has type O blood or is Rh negative.
Dr. Neeta Goli:
Just in terms of where this nomogram came from, so Bhutani, in 1999, published a study that looked at 13,000 babies born in Pennsylvania in the mid-1990s. They drew one serum bilirubin while babies were inpatient, and then one serum bilirubin after discharge. They looked at the serum bilirubin that was drawn while babies were inpatient, and then the likelihood of the post discharge bilirubin being greater than 95th percentile. They found that, for babies who are plotted out as the "low-risk" zone, so zone one, there was a 0% risk that they would come back and have a severely high bilirubin post discharge. For babies in the low intermediate risk zone, they found that they had a 2% chance of having high bilirubin after discharge. The high intermediate risk zone, or zone three, there was a 13% risk. For the high risk zone, or zone four, there was a 40% risk of them going on to develop severe hyperbilirubinemia. When we look at the Bhutani nomogram, it gives us an idea of how closely we need to follow the bilirubin or how much we need to be worried about them coming back with a significant hyperbilirubinemia that might need to be treated.
Dr. Jessica Morse:
Exactly. That can also give you a little bit of it guide on when follow-up should be arranged as well. For instance, if you have a baby that is zone two or low intermediate risk zone, you may want to follow them up in 48 to 72 hours, versus a baby that is in the high intermediate risks zone, you might want to have them follow up in 24 to 48 hours.
Dr. Neeta Goli:
And then, after we look at the Bhutani hyperbilirubinemia risk nomogram, there's another nomogram that we also use, and this is the phototherapy curve. Can you explain this a little bit more and what the difference is between the two curves?
Dr. Jessica Morse:
Yeah, so the AAP phototherapy guidelines, this is a curve that was published in the AAP in 2004, along with an exchange transfusion nomogram, don't worry more to come on that later, that also uses the infants gestational age at birth, as well as the total serum bilirubin at the time it was drawn. Again, you want to use the baby's gestational age, but also look at how old the baby was when the serum bilirubin was drawn.
Dr. Jessica Morse:
The most difficult thing about this nomogram is that there's three different lines, so we have to figure out which line to use. For instance, if you can see here, the top line here is for infants that are lower risk. Now, low risk doesn't mean that their serum bilirubin fell into the low risk or low intermediate risk category on the Bhutani curve. This is babies who are greater than or equal to 38 weeks and considered well.
Dr. Jessica Morse:
What does well mean? Well, for all intents and purposes for this curve, well means that the baby does not have any risk factors. And those risk factors include isoimmune hemolytic disease, G6PD deficiency, asphyxia, significant lethargy, temperature instability, sepsis, acidosis, and any other major illnesses. For all intents and purposes for our well newborns, a lot of our babies are going to fall into this lower risk category.
Dr. Neeta Goli:
And note for our learners, the risk that we're talking about here is risk for neurotoxicity versus the risk for Bhutani, when we were talking about risk for hyperbilirubinemia. So just so we understand the difference.
Dr. Jessica Morse:
Exactly. Again, so these are for our babies that are greater than or equal to 38 weeks and have none of the neurotoxicity risk factors.
Dr. Jessica Morse:
This next line here is medium risk. So again, medium risk is not based off of the Bhutani curve, but based off of our gestational age of our infant and neurotoxicity risk factors. This line is for our babies that are greater than or 38 weeks and have neurotoxicity risk factors, and for our late preterm babies or early term babies; those babies that are 35 weeks and 37 6/7 weeks. And then, our high risk babies are those that are our late preterm or early term infants that have neurotoxicity risk factors.
Dr. Jessica Morse:
Once you have your serum bilirubin, and you know that it's on the high side, you're going to want to go to this AAP phototherapy guideline and determine where they fall, and determine, number one, which line you want to use, whether it's a low risk baby, a medium risk baby, or a high risk baby, and then figure out how close they are to what we call phototherapy level or light level. How do you determine if a baby has isoimmune hemolytic disease? Well, if you guys remember, and we asked you to draw a cord blood workup on any baby in which mom had a type O blood type or was Rh negative. If baby's blood type comes back and is either A, B or AB, and mom had type O blood, you would also want to check for a Coombs. If that was positive, then you can be convinced that the baby has isoimmune hemolytic disease.
Dr. Jessica Morse:
Another thing to consider whenever you have ABO incompatibility, is to draw a CBC with a reticulocyte count to assess for hemolysis. Usually hemolysis is suggested if the hemoglobin is less than 12, hematocrit is less than 35 if they're term, or less than 40 if preterm, or if their retic count is greater than 6%. This suggests evidence of hemolysis. Again, so for instance, if you have a 38 week infant and they have ABO incompatibility with evidence of hemolysis, you would need to change them from the low risk line to using the medium risk line.
Dr. Neeta Goli:
Can you explain to me a little bit, what exactly is phototherapy and why do we use it? I've had some families come to me and say, "Well, my baby is jaundiced. Can I just sit with him in the sunlight? Will that help the jaundice?"
Dr. Jessica Morse:
Yeah. So sunlight and UV light can cause damage in the newborn skin. It's unclear as to what amount is safe to use. Usually, I recommend sitting with baby in a sunny window, not under direct sunlight. That's not actually what we consider phototherapy treatment. If your baby crosses the phototherapy thresholds based off of this AAP phototherapy guideline, you're going to want to put them under what we call special bili lights. It's a blue light that is in the 420 to 460ish spectrum. What this does is it converts, if you guys remember back to chemistry and the isomers, it converts it from the bilirubin from one isomer to the other. In other words, it makes it from insoluble to soluble, so that the baby can not only excrete it out in his stool, they can also excrete it in the urine.
Dr. Neeta Goli:
Okay. How do we practically manage these infants who we start under phototherapy?
Dr. Jessica Morse:
You're going to want to use your institution's specific guidelines and protocols to guide frequency of subsequent bilirubin checks. Basically you put the baby under these lights, and based off of what your institutional guidelines are and your clinical judgment. For instance, it depends on why you think this baby is needing phototherapy. For instance, if a baby is under phototherapy because they have significant breastfeeding jaundice versus a baby that is under phototherapy because they have a hemolytic jaundice due to ABO incompatibility, you might need to check one less frequently than the other. For instance, a baby that's under phototherapy due to breastfeeding jaundice, you're not anticipating a significant ongoing reason to be jaundiced. Once they get under those lights, typically their jaundice is going to resolve very quickly and not continue to rise. However, a baby who has a hemolytic jaundice due to ABO incompatibility, those maternal antibodies that are causing the breakdown of the blood cells aren't going away. So there's going to be continued hemolysis. Therefore, the bilirubin has the potential, despite being under phototherapy, to continue to rise, so you might need to check more frequently.
Dr. Neeta Goli:
You mentioned, for breastfeeding jaundice, in those cases would you typically recommend continuing breastfeeding or how do you manage feeding for those?
Dr. Jessica Morse:
You definitely want to optimize breastfeeding for sure. You want to make sure, number one, that mom is pumping, and working with a lactation consultant, and that there's no problems with latch and things like that. So you want to optimize it as much as you can. You want to optimize breastfeeding, however there may be some instances in which you would want to keep a baby under phototherapy and not allow them to breastfeed. Although, this is not ideal and not something that we want, it's actually potentially safer for the baby to continue to feed under the phototherapy lights. This is typically seen in babies that have a hemolytic jaundice, that is an ongoing hemolysis is causing increased bilirubin levels and their levels are rising despite being under a phototherapy. It would not be well for that baby to come out for 30 minutes to 45 minutes every three hours to breastfeed with mom. In that instance, you may need to have mom pump and give her expressed breast milk, and then supplement with formula to enhance excretion of the bilirubin.
Dr. Neeta Goli:
Those are typically severe cases. Those are cases where the bilirubin might be closer to the exchange transfusion level.
Dr. Jessica Morse:
Exactly.
Dr. Neeta Goli:
So not just your regular run of the mill hyperbilirubinemia.
Dr. Jessica Morse:
Exactly.
Dr. Neeta Goli:
In addition to optimizing feeding, what else should we consider when we start a baby under phototherapy?
Dr. Jessica Morse:
You also want to look at family history, make sure there are no other potentially genetic causes. And then, you also want to make sure that you draw the newborn screen per routine. Again, think of metabolic causes, and you also want to make sure that you've drawn a CBC to look at potential causes like sepsis and other issues.
Dr. Neeta Goli:
What are some potential complications from babies being under phototherapy lights?
Dr. Jessica Morse:
Generally, phototherapy is very well tolerated. Usually, the biggest complications are that infants typically don't like to be under phototherapy and away from their moms, so they tend to cry more and be a little bit more irritable. And then, they may have an increased risk for hypothermia, because they do have to be undressed, because ideally, you want as much light to be reflected onto the baby's skin as possible in order to be effective. Remember, if you are starting phototherapy, you really want to have a baseline direct bilirubin, because there is something called bronze baby syndrome that can develop if the baby has a direct hyperbilirubinemia and you place them under phototherapy. Again, phototherapy is used to treat an unconjugated or indirect hyperbilirubinemia. It is not used to treat a direct hyperbilirubinemia, and you really need to find the underlying cause for that direct hyperbilirubinemia.
Speaker 3:
So how do we know when to stop phototherapy?
Dr. Jessica Morse:
This is more where I think the art of medicine comes into play. It really is based off of, again, looking at the clinical picture of the baby and the reason why they needed phototherapy. Was it, again going back to our breastfeeding jaundice baby or our hemolytic jaundice baby, you have to look at the clinical picture. You might want to have the levels be a little bit lower for the baby that has a hemolytic jaundice than a baby that has a breastfeeding jaundice, because again, our hemolytic jaundice baby, when you stop phototherapy, the hemolysis is still going to continue. It's not going to stop. The levels would be expected to continue to go back up, versus a breastfeeding jaundice baby. I would expect, as feeding improves, and those levels are not going to rise as quickly as they would in a hemolytic jaundice baby. For our purposes, you should follow your institutional protocols. At Parkland we typically stop our phototherapy when the bilirubin is at least four points below light level.
Speaker 3:
And so, you brought up an interesting point. You often hear people talking about checking rebound bilirubins after stopping the lights. Can you explain a little bit about what that means?
Dr. Jessica Morse:
Yeah. A rebound bilirubin is one that you get several hours after stopping phototherapy. It's looking at what's the bilirubin going to rebound to after you've stopped therapy. And so, usually the AAP actually does not fully recommend routinely checking, "rebound" bilirubin levels. But again, you need to look at the clinical picture of what's going on with your baby. Again, going back to the two examples that we have, a baby that has breastfeeding jaundice, we wouldn't expect that bilirubin to jump back up very quickly, so it may not be necessary to draw a rebound bilirubin in a couple of hours, versus that neonate that has ongoing hemolysis in a hemolytic jaundice infant, you would expect those levels to go back up. So, it might be necessary, or it might be wise to check a level before you send that baby home. Again, there's no set rule. And so, you should use your clinical judgment.
Speaker 3:
Important point for our listeners is that the bilirubin doesn't increase because you've stopped the lights or the phototherapy. We're just assessing for continued rate of rise. It's not that us stopping is somehow causing it to get worse.
Dr. Jessica Morse:
No, definitely not. It's just, again, the clinical picture and what's physiologically going on with that neonate. A lot of times after stopping phototherapy, it's really wise to have that neonate follow up the very next day in clinic check on it and to recheck that bilirubin level to make sure that we're still doing okay.
Dr. Jessica Morse:
There was one thing I wanted to go back to you talking about phototherapy. What does phototherapy look like when you want to begin this treatment for your babies? Usually, it is a bank of lights that are on top of the baby. And then, you can add a blanket called a bili blanket that goes underneath the baby. The infant should only be wearing a diaper and you need eye protection for that infant. There are instances where this is done in a hospital setting. However, there are some cases in which you might consider doing phototherapy as an outpatient or in the family's home. Usually, outpatient phototherapy involves just a bili blanket and it's not nearly as effective as the in-hospital phototherapy where you use the overhead lights and the bili blanket in conjunction.
Dr. Jessica Morse:
Let's see, what else do I want to say about that? Whenever you have an infant that you have determined has an increased risk for developing significant hyperbilirubinemia in the next 24 hours or so, there are some things you need to look at. You need to look at how the baby is feeding. You need to look at whether the baby is well appearing or not. And you need to look at maternal and blood type.
Dr. Jessica Morse:
Again, going back to our previous talks, some of the things that can cause a significant hyperbilirubinemia that are most common in the newborn nursery are breastfeeding jaundice, and ABO incompatibility, and sepsis. So, you need to keep those three things in the back of your mind.
Dr. Jessica Morse:
What labs do you need to draw depending on the situation for your baby? For breastfeeding jaundice, you typically don't need to draw any labs other than a total bilirubin and a direct bilirubin. If you're worried about ABO incompatibility, you need to look at maternal blood type to see if mom is O positive. If she is, then you should get a cord blood workup, a direct Coombs, and a CBC, and a reticulocyte count. This will allow you to assess whether or not there is truly ABO incompatibility going on, if there's any significant hemolysis associated with that ABO incompatibility, and if there's a possibility that the infant is ill.
Dr. Jessica Morse:
What happens, if you have an infant that you have placed under phototherapy, the levels are continuing to rise and things are just not progressing in the direction that you would? If you have a baby that is well above the phototherapy guidelines, you want to also make sure that you look at the next nomogram and that is the AAP exchange transfusion guidelines. Again, it's very similar to the previous in the AAP phototherapy nomogram in that it has the same risk lines. Again, the top line is for infants at lower risk. Those infants are babies that are 38 weeks without neurotoxic risk factors. Medium risk, and those are infants that are greater than 38 weeks with neurotoxic risk factors, or late preterm or early term infants without neurotoxic risk factors. And then, our higher risk babies who are our late preterm or early term babies, with neurotoxic risk factors. As you can see this nomogram, the levels at which you would want to do in exchange are much, much higher than what you would do to start phototherapy.
Dr. Jessica Morse:
What is an exchange transfusion? An exchange transfusion is typically done through an umbilical line and it's where one person pulls blood out of the neonate while another person pushes whole blood into the neonate. In other words, they are exchanging the blood volume of the neonate to get rid of as much of the bilirubin as possible. You can do partial exchange transfusions. You can do double volume exchange transfusions. You can do single volume exchange transfusions. It just depends on what is going on with that neonate. Exchange transfusions are not benign and they typically carry a pretty significant morbidity mortality rate and should be avoided as best as we can.
Dr. Jessica Morse:
There are some steps that some institutions are taking before having to go to exchange transfusions depending on their reason for the significant jaundice. For example, if an infant has ABO incompatibility, it's an antibody mediated process, so the IgG antibodies had crossed the placenta, came into baby, and are now causing baby's red blood cells to be broken down. Some institutions are using IVIG, for example, to bind the maternal antibodies to slow down hemolysis. That will, in turn, allow the phototherapy lights to work, to do what they do, so that the baby can then excrete the bilirubin without having to go to an exchange transfusion.
Dr. Jessica Morse:
Typically exchange transfusions are done in the NICU and not done in the newborn nursery. If you have an infant that is very close to exchange transfusion level, typically you'll want to consult your closest NICU.
Dr. Neeta Goli:
Dr. Morris, thanks again for joining us today to talk about jaundice. I think this has been really great, so hopefully our listeners have a really thorough understanding of not just why and how babies get jaundice, but how to actually manage it when they're faced with it in the nursery. We hope that you are more confident in your management of babies with jaundice. Dr. Morris, to end the episode today, can you share with us your favorite part of your workday?
Dr. Jessica Morse:
I love being able to work with families and teaching moms about their newborns, especially those first-time moms who have all of the questions. Being able to teach her how to just swaddle and comfort a baby is really rewarding.
Dr. Neeta Goli:
It sounds wonderful. Thanks so much for joining us today.
Dr. Jessica Morse:
Thank you for having me.
Dr. Neeta Goli:
Thanks for listening to Newborn News. We hope you join us next time. If you like what you hear, make sure to subscribe and leave us a review. If you have questions, comments, feedback, or suggestions for future episodes, please email me at NewbornNews@utsouthwestern.edu. As a reminder, this content is educational and is not meant to be used as medical advice. Views or opinions expressed in this podcast are those of myself and my guests and do not necessarily reflect the views of the university.